CN1885050A - Strong magnetic filed Hall effect testing apparatus and testing method thereof - Google Patents
Strong magnetic filed Hall effect testing apparatus and testing method thereof Download PDFInfo
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- CN1885050A CN1885050A CN 200510011983 CN200510011983A CN1885050A CN 1885050 A CN1885050 A CN 1885050A CN 200510011983 CN200510011983 CN 200510011983 CN 200510011983 A CN200510011983 A CN 200510011983A CN 1885050 A CN1885050 A CN 1885050A
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Abstract
The invention relates to a Hall-effect tester of strong magnetic field, wherein said device is formed by extending sheet, electromagnet group, constant-current source, polarity control circuit, controllable stable voltage source, testing circuit, computer, three-phase alternative-current source, and temperature controller. And said testing method comprises: (1), making the extending sheet into electrode, and connecting the wires; (2), connecting three-phase alternative-current source, operating the computer control program, based on the program demand, inputting each parameter; (3), testing relative parameters in new balance temperature, when changing the sample condition temperature; (4), storing or printing the measure result.
Description
Technical field
The present invention relates to technical field of measurement and test, particularly a kind of filed Hall effect testing apparatus of high-intensity magnetic field and method of testing thereof.
Background technology
The Hall effect test is a basic method of testing in the semiconductor material research field, and it can measure many performances of semiconductor epitaxial film, as the numerical value of semiconductor material conduction type, resistivity, sheet resistance, carrier concentration, mobility etc.For semiconductor material with wide forbidden band, it is its big difficult point that is widely used and is faced that the p type mixes always.Owing to the reasons such as room of semiconductor material with wide forbidden band, the wide-band gap material of involuntary doping presents the n type usually.Must carry out heavy doping so obtain P-type material, make apparent hole concentration substantially exceed electron concentration, compoundly fall the n type charge carrier that reason such as room forms, to form the p section bar material of holoe carrier on the macroscopic view.Also handy annealing or low energy ion radiation come p section bar material is handled on the technology, make the impurity activation, reduce its energy of activation, improve hole concentration.Generally speaking, it is very little that the hole concentration of p section bar material and the electron concentration of n type are compared, little two orders of magnitude.Solid magnet is as Magnetic Field Source usually in the common Hall testing apparatus, and its magnetic induction density is very weak, hundreds of is only arranged to one or two Gauss.This is suitable for for the n section bar material of measuring high concentration, but concerning with wide bandgap semiconductor p section bar material, being difficult to obtain result accurately.Compare with high-intensity magnetic field, under very weak magnetic field, the Hall voltage that identical electric current produces is much little, owing to recording in Ai Yanhaosen effect, Nernst effect, lining---and leduc effects etc. can produce side direction voltage, and the Hall voltage that really record this moment is several composite value.The numerical error that records like this is sizable, even the material of p type can be surveyed into the n section bar material of high resistant by mistake.Have only the high-intensity magnetic field of employing, increase the Hall voltage that produces, make the voltage that is produced by above-mentioned several reasons become and can ignore, the result of measurement could be accurately.Usually the electric current computational data is regulated in employing manually in addition, often produces artificial mistake, produces a series of problem: (1) artificial reading and adjusting current error are obvious, and precision is difficult to guarantee; (2) manual control reversal makes mistakes easily; (3) artificial data is handled poor reliability, inefficiency.
Summary of the invention
Purpose of the present invention is exactly to overcome the technology and method problem that exists in the wide bandgap semiconductor Hall effect measuring equipment, design a kind of filed Hall effect testing apparatus of high-intensity magnetic field and required testing software, to realize automatic measurement, the automatic reverse of polarity, automatic data processing, carry out work accurately and easily.
The present invention has designed a kind of filed Hall effect testing apparatus of high-intensity magnetic field.This invention is characterised in that the difficulty of having considered the test of extension wide bandgap semiconductor p section bar material Hall, and the electromagnet group that has adopted high magnetic field intensity is as magnetic source, but not employing common solid permanent magnet, and adopt automatic control circuit and program.This design characteristic is: (1) high-intensity magnetic field makes the Hall voltage that produces enlarge markedly, thereby the measurement result precision improves; (2) adopt the controlled voltage stabilizing DC source of three-phase alternating current input for obtaining high-intensity magnetic field, make the adjustable and good stability of magnetic field intensity; (3) automaticity height in the measuring process has avoided causing error or wrong artificial factor, makes measurement more accurately convenient.
The filed Hall effect testing apparatus of high-intensity magnetic field type of the present invention is connected and composed by epitaxial wafer, electromagnet group, constant current source, polarity control circuit, controlled source of stable pressure, metering circuit, computing machine, three-way alternating current, attemperating unit etc.Concrete circuit connects: the output control line of computing machine is connected with polarity control circuit, controlled source of stable pressure respectively; The output line of metering circuit is connected with the input control line of computing machine; The constant current source output line is connected with the polarity control circuit incoming line; The input-output line of epitaxial wafer is connected with the output input control line of polarity control circuit respectively; The output line of controlled source of stable pressure is connected with the incoming line of electromagnet group; The output line of three-way alternating current is connected with the incoming line of controlled source of stable pressure; Attemperating unit is independently controlled.
Described metering circuit function is finished by data collecting card and analog-to-digital conversion card, and they insert the computer PCI bus interface.Data collecting card can adopt the AC6040 plate, and it has 4 road both-end analog inputs, 16 way switch amounts---8 tunnel inputs and 8 tunnel outputs.Analog-to-digital conversion card can adopt ADLINKPCI-7248's etc.
The polarity control circuit function is realized by electromagnetic relay group and operational amplifier and digital-to-analog conversion card.The instruction that computing machine sends becomes simulating signal through the digital-to-analog conversion card, gets the respective electrical magnetic relay through operational amplifier, realizes input-output line and the variation of direction of current separately on the epitaxial wafer.
Controlled source of stable pressure is by formations such as three phase rectifier module (six controllable silicons), rectification module driver, comparers.Control signal enters comparer, compares with sampling current, and comparer is given rectification driver module feedback phase shift signal, changes the controllable silicon phase place, thereby reaches stable with maintenance to the adjusting of DC voltage.
Attemperating unit is made of Dewar flask, resistance wire, thermopair, cooling duct, controller etc.
Constant current source is by being made of small-sized stabilized voltage supply.
Electromagnet group is made of large power, electrically magnet and cooling recirculation system.
During the Hall voltage of sheet sample is measured, four contact electrode ABCD are arranged, on the sheet sample as Fig. 2.During the control program operation,, at first allow the CD electrode pass to electric current by polarity control circuit, by polarity control circuit and controlled source of stable pressure, the polarity in conversion electric current and magnetic field, correspond respectively to (+I+B), (I+B), (I-B), (+I-B) four class values are measured the electric potential difference (V between the AB electrodes
AB)
1, (V
AB)
2, (V
AB)
3, (V
AB)
4, allow AB electrodes pass to electric current then automatically, correspond respectively to (+I+B), (I+B), (I-B), (+I-B) four class values are measured the electric potential difference (V between the CD probe
CD)
1, (V
CD)
2, (V
CD)
3, (V
CD)
4, change polarity chron at every turn, 500 milliseconds of automatic time delays, so that electric current and magnetic field are stable, each step is connected compact in the measuring process, produces bigger heat when helping reducing electric current and flowing through sample, by V
AB, V
CDCan calculate corresponding Hall coefficient R
HA, R
HBIf both differ and surpass ± 10%, just think that sample is uneven.Adopt the Hall coefficient of four groups of data computation can eliminate or weaken Ai Yanhaosen effect, Nernst effect, lining discipline---the error that leduc effect etc. bring effectively, improved measuring accuracy.
Principle of work of the present invention and circuit working principle are as follows: epitaxial wafer is carried out Ohm contact electrode, be placed in specimen holder, can put into Dewar flask as required and keep temperature constant, specimen holder or Dewar flask place between two magnetic poles, regulate required temperature, connecting three-way AC power opens cooling circulating water and opens computing machine, the control program of this device of operation on the pc computing machine, measure beginning: initialization, select the suitable current range, the label thickness parameter of input test sample, the number of times of input duplicate measurements, computer controlled automatic and measurement, change sample temperature on every side again, repeat said process, after measurement finishes, program is carried out each CALCULATION OF PARAMETERS, finishes test.
The filed Hall effect testing apparatus measuring process of high-intensity magnetic field of the present invention is as follows:
(1) epitaxial wafer is carried out electrode, connect lead, be placed on the specimen holder, then specimen holder is placed in the Dewar flask together with sample, feed liquid nitrogen or liquid helium to Dewar flask, come the environment temperature of measuring samples with being placed on the thermopair that is applicable to low temperature in the sample chamber, be adjusted to proper temperature, as only needing an indoor temperature measurement, Dewar flask is placed between two magnetic poles, and make two planes of the magnetic line of force perpendicular to epitaxial wafer, as only needing indoor temperature measurement, then directly specimen holder is positioned between two magnetic poles;
(2) logical three-way AC power, the operation computer-controlled program, according to the program requirement, import each parameter successively, confirm errorless after, click to measure button, the numerical value of the carrier concentration, resistivity, mobility, sheet resistance of conduction type, body or the film of epitaxial wafer etc. is measured and calculated to Automatic Program;
(3) can change the sample environment temperature, under new equilibrium temperature, continue to measure correlation parameter;
(4) measurement result is filed or print end of test (EOT).
Such design has following advantage: (1) can accurately be convenient for measuring the Hall parameter of wide bandgap semiconductor p section bar material; (2) utilize Dewar flask, liquid nitrogen or liquid helium, resistive heater, thermopair can realize that the temperature from 10K to 400K changes continuously, expanded measurement range; (3) utilize three-phase alternating current to be transformed into direct current, both produced higher DC voltage, guaranteed the stable of DC voltage again through controlled voltage stabilizing, and can be by the variation of computer control voltage.
Description of drawings
Following accompanying drawing has provided the filed Hall effect testing apparatus principle and the test flow chart of high-intensity magnetic field type of the present invention, illustrates herein and introduce to be based on all that following drawing makes an explanation.
Fig. 1 is the filed Hall effect testing apparatus structural representation of high-intensity magnetic field type of the present invention.
Fig. 2 is the electrode synoptic diagram of vanderburg method.
Fig. 3 is the testing process block diagram of this device.
Embodiment:
As seen from Figure 1, the filed Hall effect testing apparatus of a kind of high-intensity magnetic field of the present invention is connected and composed by epitaxial wafer 1, electromagnet group 2, constant current source 3, polarity control circuit 4, controlled source of stable pressure 5, metering circuit 6, computing machine 7, three-phase alternating current 8, attemperating unit 9 etc.Concrete circuit connects: the output control line of computing machine 7 is connected with polarity control circuit 4, controlled source of stable pressure 5 respectively; The output line of metering circuit 6 is connected with the input control line of computing machine 7; Constant current source 3 output lines are connected with polarity control circuit 4 incoming lines; The input-output line of epitaxial wafer 1 is connected with the output input control line of polarity control circuit 4 respectively; The output line of controlled source of stable pressure 5 is connected with the incoming line of electromagnet group 2; The output line of three-phase alternating current 8 is connected with the incoming line of controlled source of stable pressure 5; Attemperating unit 9 independent controls.
The application of as seen from Figure 2, in fact Here it is Van der Pauw's method.
As seen from Figure 3, program begins, initialization, regulate the sample environment temperature, select the reometer of suitable range, relevant informations such as the numbering of input sample, thickness and measurement number of times, regulate magnetic field intensity, measure and just carry out automatically, then alternating temperature begins new measurement under new temperature conditions, after measurement finishes, automatically carry out data processing, print or file end of test (EOT).
Specific implementation process of the present invention is as follows:
(1) electromagnet requires to produce 20000 Gausses, and circulating cooling system must be arranged, and can entrust specialized factory to make.
(2) but the intact line of used circuit board cloth is entrusted specialized factory's processing.
(3) required control program can be used high level language.
(4) used attemperating unit can be bought finished product.
Used data collecting card can adopt the AC6040 plate, and it has 4 road both-end analog inputs, 16 way switch amounts---8 tunnel inputs and 8 tunnel outputs.Analog-to-digital conversion card can adopt all can of ADLINK PCI-7248 etc.Can both on market, buy.
Claims (9)
1. the filed Hall effect testing apparatus of a high-intensity magnetic field, connected and composed by epitaxial wafer, electromagnet group, constant current source, polarity control circuit, controlled source of stable pressure, metering circuit, computing machine, three-phase alternating current, attemperating unit, concrete circuit connects: the output control line of computing machine is connected with polarity control circuit, controlled source of stable pressure input control line respectively; The output line of metering circuit is connected with the input control line of computing machine; The constant current source output line is connected with the polarity control circuit incoming line; The input-output line of epitaxial wafer is connected with the output input control line of polarity control circuit respectively; The output line of controlled source of stable pressure is connected with the incoming line of electromagnet group; The output line of three-way alternating current is connected with the incoming line of controlled source of stable pressure; Attemperating unit is independently controlled.
2. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1, it is characterized in that, metering circuit is finished by data collecting card and analog-to-digital conversion card, insert the computer PCI bus interface, data collecting card can adopt the AC6040 plate, it has 4 road both-end analog inputs, 16 way switch amounts---and 8 tunnel inputs and 8 tunnel outputs, analog-to-digital conversion card can adopt PCI-7248's.
3. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1 is characterized in that, polarity control circuit is realized by electromagnetic relay group and operational amplifier and digital-to-analog conversion card.
4. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1 is characterized in that, controlled source of stable pressure is made of three phase rectifier module, rectification module driver, comparer.
5. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1 is characterized in that, attemperating unit is made of Dewar flask, resistance wire, thermopair, cooling duct, controller.
6. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1 is characterized in that, constant current source is made of small-sized stabilized voltage supply.
7. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1 is characterized in that, electromagnet group is made of large power, electrically magnet and cooling recirculation system.
8. the filed Hall effect testing apparatus of high-intensity magnetic field as claimed in claim 1, it is characterized in that, measuring process: during the control program operation, pass through polarity control circuit, at first allow the CD electrode pass to electric current, by polarity control circuit and controlled source of stable pressure, the polarity in conversion electric current and magnetic field, correspond respectively to (+I+B), (I+B), (I-B), (+I-B) four class values are measured the electric potential difference (V between the AB electrodes
AB)
1, (V
AB)
2, (V
AB)
3, (V
AB)
4, allow AB electrodes pass to electric current then automatically, correspond respectively to (+I+B), (I+B), (I-B), (+I-B) four class values are surveyed the electromotive force (V between the CD probe
CD)
1, (V
CD)
2, (V
CD)
3, (V
CD)
4, change polarity chron at every turn, 500 milliseconds of automatic time delays, so that electric current and magnetic field are stable, each step is connected compact in the measuring process, produces bigger heat when helping reducing electric current and flowing through sample, by V
AB, V
CDCan calculate corresponding Hall coefficient R
HA, R
HBIf differing, both surpass ± 10%, just think that sample is uneven, adopt the Hall coefficient of four groups of data computation can eliminate or weaken Ai Yanhaosen effect, Nernst effect, lining discipline---the error that leduc effect etc. bring effectively, improved measuring accuracy.
The filed Hall effect testing apparatus of 9 high-intensity magnetic fields as claimed in claim 1 is characterized in that, testing procedure is as follows:
(1) epitaxial wafer is carried out electrode, connect lead, be placed on the specimen holder, then specimen holder is placed in the Dewar flask together with sample, feed liquid nitrogen or liquid helium to Dewar flask, come the environment temperature of measuring samples with being placed on the thermopair that is applicable to low temperature in the sample chamber, be adjusted to proper temperature, as only needing indoor temperature measurement, Dewar flask is placed between two magnetic poles, and make two planes of the magnetic line of force perpendicular to epitaxial wafer, as only needing indoor temperature measurement, then directly specimen holder is positioned between two magnetic poles;
(2) connect three-way AC power, the operation computer-controlled program, according to the program requirement, import each parameter successively, confirm errorless after, click to measure button, carrier concentration, resistivity, the mobility of conduction type, body or the film of epitaxial wafer, the numerical value of sheet resistance are measured and calculated to Automatic Program;
(3) can change the sample environment temperature, under new equilibrium temperature, continue to measure correlation parameter;
(4) measurement result is filed or print end of test (EOT).
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|---|---|---|---|
| CN 200510011983 CN1885050A (en) | 2005-06-23 | 2005-06-23 | Strong magnetic filed Hall effect testing apparatus and testing method thereof |
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| CN 200510011983 CN1885050A (en) | 2005-06-23 | 2005-06-23 | Strong magnetic filed Hall effect testing apparatus and testing method thereof |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101320082B (en) * | 2007-06-07 | 2010-08-18 | 勤益股份有限公司 | Hall magnetic field element test apparatus |
| CN103760484A (en) * | 2014-01-23 | 2014-04-30 | 新磊半导体科技（苏州）有限公司 | Novel method for testing back gate effect |
| CN103794526A (en) * | 2014-01-23 | 2014-05-14 | 新磊半导体科技（苏州）有限公司 | Novel Hall test method |
| CN104458590B (en) * | 2014-12-02 | 2017-04-05 | 华侨大学 | A kind of perpendicular magnetization films test device |
| CN108051646A (en) * | 2017-11-08 | 2018-05-18 | 中国计量科学研究院 | Without liquid helium quantum Hall resistance transfer device |
| CN108181567A (en) * | 2018-01-11 | 2018-06-19 | 武汉嘉仪通科技有限公司 | A kind of Hall effect tester |
| CN109116270A (en) * | 2018-06-27 | 2019-01-01 | 中国电子科技集团公司第十研究所 | The method that a kind of pair of mercury cadmium telluride pn-junction material is tested |
| CN110632509A (en) * | 2019-10-10 | 2019-12-31 | 湖北航天技术研究院计量测试技术研究所 | Hall switch test tool and test method |
| CN110879375A (en) * | 2019-11-13 | 2020-03-13 | 江阴职业技术学院 | Method for measuring and correcting output voltage error generated by side effect in Hall effect |
| CN111063065A (en) * | 2019-12-17 | 2020-04-24 | 万晖五金（深圳）有限公司 | Magnetic field lock system and magnetic field lock control method |
| CN111289928A (en) * | 2020-03-10 | 2020-06-16 | 无锡力芯微电子股份有限公司 | Hall device testing system and testing method |
| CN112198469A (en) * | 2020-09-14 | 2021-01-08 | 东南大学 | Hall effect automatic measuring system and measuring method thereof |
| CN114324980A (en) * | 2022-03-14 | 2022-04-12 | 南京中旭电子科技有限公司 | Multi-parameter testing method for multi-channel Hall sensor with expansion function |
| CN115327456A (en) * | 2022-09-01 | 2022-11-11 | 中国矿业大学 | Method for measuring spin Hall angle of n-type gallium arsenide-doped semiconductor at room temperature |
| CN115963148A (en) * | 2022-11-24 | 2023-04-14 | 安徽光智科技有限公司 | Hall measurement device and method based on mercury cadmium telluride material |
-
2005
- 2005-06-23 CN CN 200510011983 patent/CN1885050A/en active Pending
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101320082B (en) * | 2007-06-07 | 2010-08-18 | 勤益股份有限公司 | Hall magnetic field element test apparatus |
| CN103760484A (en) * | 2014-01-23 | 2014-04-30 | 新磊半导体科技（苏州）有限公司 | Novel method for testing back gate effect |
| CN103794526A (en) * | 2014-01-23 | 2014-05-14 | 新磊半导体科技（苏州）有限公司 | Novel Hall test method |
| CN103760484B (en) * | 2014-01-23 | 2015-04-22 | 新磊半导体科技（苏州）有限公司 | Novel method for testing back gate effect |
| CN104458590B (en) * | 2014-12-02 | 2017-04-05 | 华侨大学 | A kind of perpendicular magnetization films test device |
| CN108051646A (en) * | 2017-11-08 | 2018-05-18 | 中国计量科学研究院 | Without liquid helium quantum Hall resistance transfer device |
| CN108181567A (en) * | 2018-01-11 | 2018-06-19 | 武汉嘉仪通科技有限公司 | A kind of Hall effect tester |
| CN109116270B (en) * | 2018-06-27 | 2021-04-30 | 中国电子科技集团公司第十一研究所 | Method for testing mercury cadmium telluride pn junction material |
| CN109116270A (en) * | 2018-06-27 | 2019-01-01 | 中国电子科技集团公司第十研究所 | The method that a kind of pair of mercury cadmium telluride pn-junction material is tested |
| CN110632509A (en) * | 2019-10-10 | 2019-12-31 | 湖北航天技术研究院计量测试技术研究所 | Hall switch test tool and test method |
| CN110879375B (en) * | 2019-11-13 | 2022-03-04 | 江阴职业技术学院 | Method for measuring and correcting output voltage error generated by side effect in Hall effect |
| CN110879375A (en) * | 2019-11-13 | 2020-03-13 | 江阴职业技术学院 | Method for measuring and correcting output voltage error generated by side effect in Hall effect |
| CN111063065B (en) * | 2019-12-17 | 2021-03-12 | 万晖五金（深圳）有限公司 | Magnetic field lock system and magnetic field lock control method |
| CN111063065A (en) * | 2019-12-17 | 2020-04-24 | 万晖五金（深圳）有限公司 | Magnetic field lock system and magnetic field lock control method |
| CN111289928A (en) * | 2020-03-10 | 2020-06-16 | 无锡力芯微电子股份有限公司 | Hall device testing system and testing method |
| CN112198469A (en) * | 2020-09-14 | 2021-01-08 | 东南大学 | Hall effect automatic measuring system and measuring method thereof |
| CN112198469B (en) * | 2020-09-14 | 2023-11-07 | 东南大学 | Hall effect automatic measurement system and measurement method thereof |
| CN114324980A (en) * | 2022-03-14 | 2022-04-12 | 南京中旭电子科技有限公司 | Multi-parameter testing method for multi-channel Hall sensor with expansion function |
| CN114324980B (en) * | 2022-03-14 | 2022-05-24 | 南京中旭电子科技有限公司 | Multi-parameter testing method for multi-channel Hall sensor with expansion function |
| CN115327456A (en) * | 2022-09-01 | 2022-11-11 | 中国矿业大学 | Method for measuring spin Hall angle of n-type gallium arsenide-doped semiconductor at room temperature |
| CN115327456B (en) * | 2022-09-01 | 2023-05-12 | 中国矿业大学 | Method for measuring spin hall angle of n-type doped gallium arsenide semiconductor at room temperature |
| CN115963148A (en) * | 2022-11-24 | 2023-04-14 | 安徽光智科技有限公司 | Hall measurement device and method based on mercury cadmium telluride material |
| CN115963148B (en) * | 2022-11-24 | 2023-10-31 | 安徽光智科技有限公司 | Hall measuring device and method based on tellurium-cadmium-mercury material |
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